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A modern aircraft wing contains many complex pipes and ducts which, amongst other functions, form the fuel management and bleed air systems. These parts are often fabricated from thin sheet material using a combination of forming and welding and the manufacturing process is predominantly manual requiring highly skilled labor. Since each wing may only contain one or two of each part type the product volumes are very low, typically a few hundred per year. This means that conventional mass production approaches used in, for example the automotive industry, are not economically viable and the parts are thus disproportionately expensive. The current fabrication process involves splitting the component into parts that can be press formed from sheet, laser trimmed and then manually welded together in a fixture. This process requires a perfect fit between the parts whose quality is reliant on the initial forming process.

This paper describes the current state of development of a highly flexible assembly and auto-riveting system based around multiple robots and compact and innovative riveting and assembly end-effectors. The riveting end-effectors are capable of drilling, countersinking, sealing and upsetting operations. The assembly end-effectors are re-configurable and can handle ant stringer or frame on a Bombardier Aerospace CRJ700 fuselage panel. The cell is also equipped with non-contact metrology systems that are used to compensate for compliance and remove the requirement for large and complex fixtures. The riveting system has been fully evaluated and a number of test coupons submitted for testing. Detailed analysis of these has proved that the resulting riveted joints are of production quality. The final system will be non-product specific allowing a single cell to produce a number of different aircraft components.

The use of simulation is a recognised part of the design process for automated systems and this has been particularly so in the development of the very large machines used in aero-structure manufacture. As part of an ongoing research project at the University of Nottingham a flexible rapid assembly cell is currently being developed that will be capable of manufacturing a number of different aero-structure sub-assemblies. The individual technologies required such as riveting, drilling and assembly have been developed and the complete cell is now being realised. A key enabler for the realisation of the cell has been the use of simulation, both in the development stage and as a central component of the operating and programming systems. This paper will describe the application of simulation techniques within the cell and during its design.

This paper describes the development of highly flexible auto-riveting system based around multiple Tricept robots and compact and innovative end-effectors. The end-effectors are capable of performing drilling, countersinking, sealing and riveting operations. The key to the success of the system is the high repeatability and stiffness of the Tricept robot allied with a very compact end-effector. The compact end-effector allows riveting to be performed in confined areas thus increasing the number of rivets that can be inserted automatically. The end-effectors also contain a significant amount of process monitoring sensors to enable automated in-process checks and quality measurement.

Significant effort has been applied to the introduction of automation for the structural assembly of aircraft. However, the equipping of the aircraft with internal services such as hydraulics, fuel, bleed-air and electrics and the attachment of movables such as ailerons and flaps remains almost exclusively manual and little research has been directed towards it. The problem is that the process requires lengthy assembly methods and there are many complex tasks which require high levels of dexterity and judgement from human operators. The parts used are prone to tolerance stack-ups, the tolerance for mating parts is extremely tight (sub-millimetre) and access is very poor. All of these make the application of conventional automation almost impossible. A possible solution is flexible metrology assisted collaborative assembly. This aims to optimise the assembly processes by using a robot to position the parts whilst an operator performs the fixing process.

As part of an ongoing collaborative research project between The University of Nottingham and Bombardier Aerospace a pair of end-effectors have been developed that allow solid riveting of aircraft fuselage panels to be performed using conventional robots. This paper describes the development and performance testing of a compact process monitoring system and its integration into the riveting end-effector and testing. The developed process monitoring system is based around a miniature CCD camera combined with a novel structured lighting system. The combination of the structured lighting system with image processing techniques means that good quality images of the drilled and countersunk holes and rivets can be obtained despite the confined environment and highly reflective materials involved. The impact of the system on the overall cycle time is also minimised.

In the civil aircraft industry there is a continuous drive to increase the aircraft production rate, particularly for single aisle aircraft where there is a large backlog of orders. One of the bottlenecks is the wing assembly process which is largely manual due to the complexity of the task and the limited accessibility. The presented work describes a general wing build approach for both structure and systems equipping operations. A modified build philosophy is then proposed, concerned with large component pre-equipping, such as skins, spars or ribs. The approach benefits from an offloading of the systems equipping phase and allowing for higher flexibility to organize the pre-equipping stations as separate entities from the overall production line. Its application is presented in the context of an industrial project focused on selecting feasible system candidates for a fixed wing design, based on assembly consideration risks for tooling, interference and access.